textproduct: Quad Cities

KEY MESSAGES

- Scattered storms possible this morning primarily west of the Mississippi River. Heavy rain and gusty winds up to 50 mph will be the primary threats. - Humid but not as hot today, with highs only in the 80s. There will be dry periods as well, with lower coverage of storms expected for evening fireworks displays.

- Additional showers/storms Sunday, before drying out early next week.

SHORT TERM /THROUGH TONIGHT/

Issued at 245 AM CDT Sat Jul 4 2026

Morning water vapor imagery shows two distinct shortwaves, one over southeast NE and another one over eastern SD. Ahead of these waves, strong upper level divergence along a 850mb moisture gradient brought more storm development over central IA, especially over Story county where another 4+ inches has fallen in just 3 hrs.

A rather challenging forecast continues today, with regards to storm timing and evolution. Most CAMs have not been helpful and have relied heavily on observational trends and SPC mesoanalysis for the near-term forecast. Current thinking is the storms over central IA will make their way into eastern IA by daybreak in a decaying mode, as the LLJ weakens. Some dry hours is certainly possible for 4th of July activities mid-late morning from west to east across the region. This afternoon, additional storms are expected to develop primarily from the outflow boundaries from last evening's storms. A similar environment will be in place from last evening (moist BL, favorable thermodynamics, weak deep layer shear) leading to slow storm motions. Where exactly these storms fire and linger is still uncertain and for this reason, opted to expand and extend the Flood Watch for flash flooding until 00z. While recent CAM trends seem to suggest a lower coverage of storms this afternoon/evening still felt it prudent to keep the watch going during the holiday. The 00z REFS 24-hr QPF PMM has 2-4 inch stripes falling roughly between the Hwy 20 and I-80 corridors. In addition to a flash flood threat, this will likely lead to renewed rises on tributary rivers. Please see latest flood statements and forecasts for details.

Some good news though, is the overall coverage of storms after 7pm is looking much lower than last evening resulting in a higher confidence dry forecast for most late evening for fireworks displays! Overnight lows to drop into the upper 60s.

LONG TERM /SUNDAY THROUGH FRIDAY/

Issued at 245 AM CDT Sat Jul 4 2026

Sunday...shortwave trof to move through in the morning, bringing chance PoPs for scattered showers and storms through the afternoon hours. Dewpoints in the upper 60s/low 70s will keep humid conditions around through the rest of the weekend. However, it will not be as hot, with highs in the low to mid 80s.

Next week...broad ridging aloft over the central CONUS to bring mainly dry and seasonable conditions. Active storm track appears to be just to our north over the Dakotas and MN until Wednesday night/Thursday when a cold front will bring us our next chance for widespread precipitation.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 554 AM CDT Sat Jul 4 2026

VFR is expected to prevail for the majority of the TAF period, however the first hour from 12-13z will contain some -TSRA and -SHRA which looks to depart fairly quickly. Skies remain OVC/BKN but mostly VFR once it ends, with SCT/BKN040-060 level CIGS after 19z lasting through 02z. Alongside the mid level clouds, -TSRA remains possible throughout the period, with the highest confidence window being 21-00z, however they will be pop up and relatively short lived. While VFR is expected to prevail for most of the period, windows of MVFR/IFR are possible mainly with -TSRA. Winds will become light and somewhat variable after the -TSRA/-SHRA departs early in the period, favoring 030-060 at or below 05kts.

DVN WATCHES/WARNINGS/ADVISORIES

IA...Flood Watch through this evening for IAZ040>042-051>054- 063>068-076>078-087>089. IL...Flood Watch through this evening for ILZ015-024. MO...None.